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The pests' natural habitat is warm, damp and humid, with frequent small lakes and pools, and wide, shallow seas.
Despite the name 'void pest' they do not inhabit the void(as like abyssal creatures inhabit the Abyss), but rather live on a separate plane accessed via the Void through portals.
The topography is mostly flat and features more soil than rock. There are likely considerable streches of jungle in the equatorial regions, and narrow bands of forest - deciduous though coniferous - towards the poles.
Fauna of the world are either enormous pack and herd creatures (safety in numbers when the apex species is a swarming society) or tiny, fast and solitary.
Pests are best known in Gielinor as a result of the recent spate of invasions through a series of portals. The Void Knight order has been successfully holding these back with the aid of a number of adventurers, but the question remains unanswered as to why the attacks are taking place.
With the pests being intelligent creatures, they must have a reason for attempting to spread to a world which is in all ways inferior to their own, for their species.
Pest society appears to be of a nature of a strongly-varied insect hive. The identified castes of pest are queen, soldier, drone and worker.
There appears to be a form of communication between all pests ( a hive mind, perhaps) and each is capable of locating its fellows at considerable range.
Smaller pests exhibit strongly instinctive behaviors, despite evidence that even the smallest have some degree of sapience. Spinners, for example, will attempt to restore the strength of a failing void portal even in an active combat environment.
The Void Pest Queen leads the hive, controlling her underlings through some form of communication as of yet unknown. Indeed, very little is known of queens, as no portal large enough for them to enter our world has yet been created and an expedition to the other side of the Void is currently unwise.
The void shifter is a shock troop among pests, a swift melee fighter capable of short-range teleports to close on prey or to carry an ally out of danger. The void torcher represents a curious anomaly, uniquely capable of magic attacks where most pests use physical means. Void brawlers are huge beasts, thought to be the least intelligent pests, but their bulk makes them fine defenders. A void defiler is the ranger of the pests' armies. Flinging bone barbs over vast distances, they have accounted for many Void Knight casualties in recent conflicts.
Void drones, tiny and agile, are the scouts of the pest force. The Void Knights do not often face these pests; for now, the scouting seems mostly done. The void splatter is a strange, sad being; two thirds of their body is a sac of acid. They may be used in the nest to dissolve obstacles; in combat, they self destruct for the hive, showering foes with acid in a suicide attack. Void ravagers are often confused for solders, as they are seen in the front lines of swarm invasions. They are poor fighters, however, and their oversized claws are more suited to nest building and destroying fortifications.
Void spinners exude and rely on portal energy. They are a familiar sight frantically repairing the invasion portals on the conflict islands. Strangely, they seem incapable of opening portals on their own, which suggests that these may have another source.
It is purely conjecture whether the caste tentatively named 'servitor' really exists; logic suggests that the logistics of running the hive and tending the queen would depend of a purely general worker.
A void leech fills the same role within a pest hive as honey ant vessels, with the exception that the food/energy supply is stored externally.
The leech will secrete a thich layer of sticky mucus onto the walls of the burrow and, as it drains the energy from surrounding living things, will snip off hardened, energy-rich chunks of goo and place it in a pile for void servitors to take to injured soldiers or to spinners to 'supercharge' them just prior to a raid.
Jessika, Wintumber 29, 168.